linux/net/dsa/port.c
Russell King 8640f8dc6d net: dsa: fix phylink_start()/phylink_stop() calls
Place phylink_start()/phylink_stop() inside dsa_port_enable() and
dsa_port_disable(), which ensures that we call phylink_stop() before
tearing down phylink - which is a documented requirement.  Failure
to do so can cause use-after-free bugs.

Fixes: 0e27921816 ("net: dsa: Use PHYLINK for the CPU/DSA ports")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-03 15:45:49 -08:00

738 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Handling of a single switch port
*
* Copyright (c) 2017 Savoir-faire Linux Inc.
* Vivien Didelot <vivien.didelot@savoirfairelinux.com>
*/
#include <linux/if_bridge.h>
#include <linux/notifier.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include "dsa_priv.h"
static int dsa_port_notify(const struct dsa_port *dp, unsigned long e, void *v)
{
struct raw_notifier_head *nh = &dp->ds->dst->nh;
int err;
err = raw_notifier_call_chain(nh, e, v);
return notifier_to_errno(err);
}
int dsa_port_set_state(struct dsa_port *dp, u8 state,
struct switchdev_trans *trans)
{
struct dsa_switch *ds = dp->ds;
int port = dp->index;
if (switchdev_trans_ph_prepare(trans))
return ds->ops->port_stp_state_set ? 0 : -EOPNOTSUPP;
if (ds->ops->port_stp_state_set)
ds->ops->port_stp_state_set(ds, port, state);
if (ds->ops->port_fast_age) {
/* Fast age FDB entries or flush appropriate forwarding database
* for the given port, if we are moving it from Learning or
* Forwarding state, to Disabled or Blocking or Listening state.
*/
if ((dp->stp_state == BR_STATE_LEARNING ||
dp->stp_state == BR_STATE_FORWARDING) &&
(state == BR_STATE_DISABLED ||
state == BR_STATE_BLOCKING ||
state == BR_STATE_LISTENING))
ds->ops->port_fast_age(ds, port);
}
dp->stp_state = state;
return 0;
}
static void dsa_port_set_state_now(struct dsa_port *dp, u8 state)
{
int err;
err = dsa_port_set_state(dp, state, NULL);
if (err)
pr_err("DSA: failed to set STP state %u (%d)\n", state, err);
}
int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy)
{
struct dsa_switch *ds = dp->ds;
int port = dp->index;
int err;
if (ds->ops->port_enable) {
err = ds->ops->port_enable(ds, port, phy);
if (err)
return err;
}
if (!dp->bridge_dev)
dsa_port_set_state_now(dp, BR_STATE_FORWARDING);
if (dp->pl)
phylink_start(dp->pl);
return 0;
}
int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy)
{
int err;
rtnl_lock();
err = dsa_port_enable_rt(dp, phy);
rtnl_unlock();
return err;
}
void dsa_port_disable_rt(struct dsa_port *dp)
{
struct dsa_switch *ds = dp->ds;
int port = dp->index;
if (dp->pl)
phylink_stop(dp->pl);
if (!dp->bridge_dev)
dsa_port_set_state_now(dp, BR_STATE_DISABLED);
if (ds->ops->port_disable)
ds->ops->port_disable(ds, port);
}
void dsa_port_disable(struct dsa_port *dp)
{
rtnl_lock();
dsa_port_disable_rt(dp);
rtnl_unlock();
}
int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br)
{
struct dsa_notifier_bridge_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.br = br,
};
int err;
/* Set the flooding mode before joining the port in the switch */
err = dsa_port_bridge_flags(dp, BR_FLOOD | BR_MCAST_FLOOD, NULL);
if (err)
return err;
/* Here the interface is already bridged. Reflect the current
* configuration so that drivers can program their chips accordingly.
*/
dp->bridge_dev = br;
err = dsa_port_notify(dp, DSA_NOTIFIER_BRIDGE_JOIN, &info);
/* The bridging is rolled back on error */
if (err) {
dsa_port_bridge_flags(dp, 0, NULL);
dp->bridge_dev = NULL;
}
return err;
}
void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
{
struct dsa_notifier_bridge_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.br = br,
};
int err;
/* Here the port is already unbridged. Reflect the current configuration
* so that drivers can program their chips accordingly.
*/
dp->bridge_dev = NULL;
err = dsa_port_notify(dp, DSA_NOTIFIER_BRIDGE_LEAVE, &info);
if (err)
pr_err("DSA: failed to notify DSA_NOTIFIER_BRIDGE_LEAVE\n");
/* Port is leaving the bridge, disable flooding */
dsa_port_bridge_flags(dp, 0, NULL);
/* Port left the bridge, put in BR_STATE_DISABLED by the bridge layer,
* so allow it to be in BR_STATE_FORWARDING to be kept functional
*/
dsa_port_set_state_now(dp, BR_STATE_FORWARDING);
}
static bool dsa_port_can_apply_vlan_filtering(struct dsa_port *dp,
bool vlan_filtering)
{
struct dsa_switch *ds = dp->ds;
int i;
if (!ds->vlan_filtering_is_global)
return true;
/* For cases where enabling/disabling VLAN awareness is global to the
* switch, we need to handle the case where multiple bridges span
* different ports of the same switch device and one of them has a
* different setting than what is being requested.
*/
for (i = 0; i < ds->num_ports; i++) {
struct net_device *other_bridge;
other_bridge = dsa_to_port(ds, i)->bridge_dev;
if (!other_bridge)
continue;
/* If it's the same bridge, it also has same
* vlan_filtering setting => no need to check
*/
if (other_bridge == dp->bridge_dev)
continue;
if (br_vlan_enabled(other_bridge) != vlan_filtering) {
dev_err(ds->dev, "VLAN filtering is a global setting\n");
return false;
}
}
return true;
}
int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
struct switchdev_trans *trans)
{
struct dsa_switch *ds = dp->ds;
int err;
/* bridge skips -EOPNOTSUPP, so skip the prepare phase */
if (switchdev_trans_ph_prepare(trans))
return 0;
if (!ds->ops->port_vlan_filtering)
return 0;
if (!dsa_port_can_apply_vlan_filtering(dp, vlan_filtering))
return -EINVAL;
if (dsa_port_is_vlan_filtering(dp) == vlan_filtering)
return 0;
err = ds->ops->port_vlan_filtering(ds, dp->index,
vlan_filtering);
if (err)
return err;
if (ds->vlan_filtering_is_global)
ds->vlan_filtering = vlan_filtering;
else
dp->vlan_filtering = vlan_filtering;
return 0;
}
int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock,
struct switchdev_trans *trans)
{
unsigned long ageing_jiffies = clock_t_to_jiffies(ageing_clock);
unsigned int ageing_time = jiffies_to_msecs(ageing_jiffies);
struct dsa_notifier_ageing_time_info info = {
.ageing_time = ageing_time,
.trans = trans,
};
if (switchdev_trans_ph_prepare(trans))
return dsa_port_notify(dp, DSA_NOTIFIER_AGEING_TIME, &info);
dp->ageing_time = ageing_time;
return dsa_port_notify(dp, DSA_NOTIFIER_AGEING_TIME, &info);
}
int dsa_port_pre_bridge_flags(const struct dsa_port *dp, unsigned long flags,
struct switchdev_trans *trans)
{
struct dsa_switch *ds = dp->ds;
if (!ds->ops->port_egress_floods ||
(flags & ~(BR_FLOOD | BR_MCAST_FLOOD)))
return -EINVAL;
return 0;
}
int dsa_port_bridge_flags(const struct dsa_port *dp, unsigned long flags,
struct switchdev_trans *trans)
{
struct dsa_switch *ds = dp->ds;
int port = dp->index;
int err = 0;
if (switchdev_trans_ph_prepare(trans))
return 0;
if (ds->ops->port_egress_floods)
err = ds->ops->port_egress_floods(ds, port, flags & BR_FLOOD,
flags & BR_MCAST_FLOOD);
return err;
}
int dsa_port_mrouter(struct dsa_port *dp, bool mrouter,
struct switchdev_trans *trans)
{
struct dsa_switch *ds = dp->ds;
int port = dp->index;
if (switchdev_trans_ph_prepare(trans))
return ds->ops->port_egress_floods ? 0 : -EOPNOTSUPP;
return ds->ops->port_egress_floods(ds, port, true, mrouter);
}
int dsa_port_fdb_add(struct dsa_port *dp, const unsigned char *addr,
u16 vid)
{
struct dsa_notifier_fdb_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.addr = addr,
.vid = vid,
};
return dsa_port_notify(dp, DSA_NOTIFIER_FDB_ADD, &info);
}
int dsa_port_fdb_del(struct dsa_port *dp, const unsigned char *addr,
u16 vid)
{
struct dsa_notifier_fdb_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.addr = addr,
.vid = vid,
};
return dsa_port_notify(dp, DSA_NOTIFIER_FDB_DEL, &info);
}
int dsa_port_fdb_dump(struct dsa_port *dp, dsa_fdb_dump_cb_t *cb, void *data)
{
struct dsa_switch *ds = dp->ds;
int port = dp->index;
if (!ds->ops->port_fdb_dump)
return -EOPNOTSUPP;
return ds->ops->port_fdb_dump(ds, port, cb, data);
}
int dsa_port_mdb_add(const struct dsa_port *dp,
const struct switchdev_obj_port_mdb *mdb,
struct switchdev_trans *trans)
{
struct dsa_notifier_mdb_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.trans = trans,
.mdb = mdb,
};
return dsa_port_notify(dp, DSA_NOTIFIER_MDB_ADD, &info);
}
int dsa_port_mdb_del(const struct dsa_port *dp,
const struct switchdev_obj_port_mdb *mdb)
{
struct dsa_notifier_mdb_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.mdb = mdb,
};
return dsa_port_notify(dp, DSA_NOTIFIER_MDB_DEL, &info);
}
int dsa_port_vlan_add(struct dsa_port *dp,
const struct switchdev_obj_port_vlan *vlan,
struct switchdev_trans *trans)
{
struct dsa_notifier_vlan_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.trans = trans,
.vlan = vlan,
};
return dsa_port_notify(dp, DSA_NOTIFIER_VLAN_ADD, &info);
}
int dsa_port_vlan_del(struct dsa_port *dp,
const struct switchdev_obj_port_vlan *vlan)
{
struct dsa_notifier_vlan_info info = {
.sw_index = dp->ds->index,
.port = dp->index,
.vlan = vlan,
};
return dsa_port_notify(dp, DSA_NOTIFIER_VLAN_DEL, &info);
}
int dsa_port_vid_add(struct dsa_port *dp, u16 vid, u16 flags)
{
struct switchdev_obj_port_vlan vlan = {
.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
.flags = flags,
.vid_begin = vid,
.vid_end = vid,
};
struct switchdev_trans trans;
int err;
trans.ph_prepare = true;
err = dsa_port_vlan_add(dp, &vlan, &trans);
if (err)
return err;
trans.ph_prepare = false;
return dsa_port_vlan_add(dp, &vlan, &trans);
}
EXPORT_SYMBOL(dsa_port_vid_add);
int dsa_port_vid_del(struct dsa_port *dp, u16 vid)
{
struct switchdev_obj_port_vlan vlan = {
.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
.vid_begin = vid,
.vid_end = vid,
};
return dsa_port_vlan_del(dp, &vlan);
}
EXPORT_SYMBOL(dsa_port_vid_del);
static struct phy_device *dsa_port_get_phy_device(struct dsa_port *dp)
{
struct device_node *phy_dn;
struct phy_device *phydev;
phy_dn = of_parse_phandle(dp->dn, "phy-handle", 0);
if (!phy_dn)
return NULL;
phydev = of_phy_find_device(phy_dn);
if (!phydev) {
of_node_put(phy_dn);
return ERR_PTR(-EPROBE_DEFER);
}
of_node_put(phy_dn);
return phydev;
}
static void dsa_port_phylink_validate(struct phylink_config *config,
unsigned long *supported,
struct phylink_link_state *state)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
struct dsa_switch *ds = dp->ds;
if (!ds->ops->phylink_validate)
return;
ds->ops->phylink_validate(ds, dp->index, supported, state);
}
static void dsa_port_phylink_mac_pcs_get_state(struct phylink_config *config,
struct phylink_link_state *state)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
struct dsa_switch *ds = dp->ds;
/* Only called for inband modes */
if (!ds->ops->phylink_mac_link_state) {
state->link = 0;
return;
}
if (ds->ops->phylink_mac_link_state(ds, dp->index, state) < 0)
state->link = 0;
}
static void dsa_port_phylink_mac_config(struct phylink_config *config,
unsigned int mode,
const struct phylink_link_state *state)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
struct dsa_switch *ds = dp->ds;
if (!ds->ops->phylink_mac_config)
return;
ds->ops->phylink_mac_config(ds, dp->index, mode, state);
}
static void dsa_port_phylink_mac_an_restart(struct phylink_config *config)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
struct dsa_switch *ds = dp->ds;
if (!ds->ops->phylink_mac_an_restart)
return;
ds->ops->phylink_mac_an_restart(ds, dp->index);
}
static void dsa_port_phylink_mac_link_down(struct phylink_config *config,
unsigned int mode,
phy_interface_t interface)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
struct phy_device *phydev = NULL;
struct dsa_switch *ds = dp->ds;
if (dsa_is_user_port(ds, dp->index))
phydev = dp->slave->phydev;
if (!ds->ops->phylink_mac_link_down) {
if (ds->ops->adjust_link && phydev)
ds->ops->adjust_link(ds, dp->index, phydev);
return;
}
ds->ops->phylink_mac_link_down(ds, dp->index, mode, interface);
}
static void dsa_port_phylink_mac_link_up(struct phylink_config *config,
unsigned int mode,
phy_interface_t interface,
struct phy_device *phydev)
{
struct dsa_port *dp = container_of(config, struct dsa_port, pl_config);
struct dsa_switch *ds = dp->ds;
if (!ds->ops->phylink_mac_link_up) {
if (ds->ops->adjust_link && phydev)
ds->ops->adjust_link(ds, dp->index, phydev);
return;
}
ds->ops->phylink_mac_link_up(ds, dp->index, mode, interface, phydev);
}
const struct phylink_mac_ops dsa_port_phylink_mac_ops = {
.validate = dsa_port_phylink_validate,
.mac_pcs_get_state = dsa_port_phylink_mac_pcs_get_state,
.mac_config = dsa_port_phylink_mac_config,
.mac_an_restart = dsa_port_phylink_mac_an_restart,
.mac_link_down = dsa_port_phylink_mac_link_down,
.mac_link_up = dsa_port_phylink_mac_link_up,
};
static int dsa_port_setup_phy_of(struct dsa_port *dp, bool enable)
{
struct dsa_switch *ds = dp->ds;
struct phy_device *phydev;
int port = dp->index;
int err = 0;
phydev = dsa_port_get_phy_device(dp);
if (!phydev)
return 0;
if (IS_ERR(phydev))
return PTR_ERR(phydev);
if (enable) {
err = genphy_resume(phydev);
if (err < 0)
goto err_put_dev;
err = genphy_read_status(phydev);
if (err < 0)
goto err_put_dev;
} else {
err = genphy_suspend(phydev);
if (err < 0)
goto err_put_dev;
}
if (ds->ops->adjust_link)
ds->ops->adjust_link(ds, port, phydev);
dev_dbg(ds->dev, "enabled port's phy: %s", phydev_name(phydev));
err_put_dev:
put_device(&phydev->mdio.dev);
return err;
}
static int dsa_port_fixed_link_register_of(struct dsa_port *dp)
{
struct device_node *dn = dp->dn;
struct dsa_switch *ds = dp->ds;
struct phy_device *phydev;
int port = dp->index;
phy_interface_t mode;
int err;
err = of_phy_register_fixed_link(dn);
if (err) {
dev_err(ds->dev,
"failed to register the fixed PHY of port %d\n",
port);
return err;
}
phydev = of_phy_find_device(dn);
err = of_get_phy_mode(dn, &mode);
if (err)
mode = PHY_INTERFACE_MODE_NA;
phydev->interface = mode;
genphy_read_status(phydev);
if (ds->ops->adjust_link)
ds->ops->adjust_link(ds, port, phydev);
put_device(&phydev->mdio.dev);
return 0;
}
static int dsa_port_phylink_register(struct dsa_port *dp)
{
struct dsa_switch *ds = dp->ds;
struct device_node *port_dn = dp->dn;
phy_interface_t mode;
int err;
err = of_get_phy_mode(port_dn, &mode);
if (err)
mode = PHY_INTERFACE_MODE_NA;
dp->pl_config.dev = ds->dev;
dp->pl_config.type = PHYLINK_DEV;
dp->pl_config.pcs_poll = ds->pcs_poll;
dp->pl = phylink_create(&dp->pl_config, of_fwnode_handle(port_dn),
mode, &dsa_port_phylink_mac_ops);
if (IS_ERR(dp->pl)) {
pr_err("error creating PHYLINK: %ld\n", PTR_ERR(dp->pl));
return PTR_ERR(dp->pl);
}
err = phylink_of_phy_connect(dp->pl, port_dn, 0);
if (err && err != -ENODEV) {
pr_err("could not attach to PHY: %d\n", err);
goto err_phy_connect;
}
return 0;
err_phy_connect:
phylink_destroy(dp->pl);
return err;
}
int dsa_port_link_register_of(struct dsa_port *dp)
{
struct dsa_switch *ds = dp->ds;
if (!ds->ops->adjust_link)
return dsa_port_phylink_register(dp);
dev_warn(ds->dev,
"Using legacy PHYLIB callbacks. Please migrate to PHYLINK!\n");
if (of_phy_is_fixed_link(dp->dn))
return dsa_port_fixed_link_register_of(dp);
else
return dsa_port_setup_phy_of(dp, true);
}
void dsa_port_link_unregister_of(struct dsa_port *dp)
{
struct dsa_switch *ds = dp->ds;
if (!ds->ops->adjust_link) {
rtnl_lock();
phylink_disconnect_phy(dp->pl);
rtnl_unlock();
phylink_destroy(dp->pl);
return;
}
if (of_phy_is_fixed_link(dp->dn))
of_phy_deregister_fixed_link(dp->dn);
else
dsa_port_setup_phy_of(dp, false);
}
int dsa_port_get_phy_strings(struct dsa_port *dp, uint8_t *data)
{
struct phy_device *phydev;
int ret = -EOPNOTSUPP;
if (of_phy_is_fixed_link(dp->dn))
return ret;
phydev = dsa_port_get_phy_device(dp);
if (IS_ERR_OR_NULL(phydev))
return ret;
ret = phy_ethtool_get_strings(phydev, data);
put_device(&phydev->mdio.dev);
return ret;
}
EXPORT_SYMBOL_GPL(dsa_port_get_phy_strings);
int dsa_port_get_ethtool_phy_stats(struct dsa_port *dp, uint64_t *data)
{
struct phy_device *phydev;
int ret = -EOPNOTSUPP;
if (of_phy_is_fixed_link(dp->dn))
return ret;
phydev = dsa_port_get_phy_device(dp);
if (IS_ERR_OR_NULL(phydev))
return ret;
ret = phy_ethtool_get_stats(phydev, NULL, data);
put_device(&phydev->mdio.dev);
return ret;
}
EXPORT_SYMBOL_GPL(dsa_port_get_ethtool_phy_stats);
int dsa_port_get_phy_sset_count(struct dsa_port *dp)
{
struct phy_device *phydev;
int ret = -EOPNOTSUPP;
if (of_phy_is_fixed_link(dp->dn))
return ret;
phydev = dsa_port_get_phy_device(dp);
if (IS_ERR_OR_NULL(phydev))
return ret;
ret = phy_ethtool_get_sset_count(phydev);
put_device(&phydev->mdio.dev);
return ret;
}
EXPORT_SYMBOL_GPL(dsa_port_get_phy_sset_count);